Method and apparatus for burning fuel



May' 31 1927.

- 1,630,387 D. s. JAcoBus METHOD AND .AEPARATUs'-.FOR BURNING- FUEL Filed Julyls, 1921 i rw A ATTORNY'S,

i enriched air to accomplish the desiredresults.

Patented May 31,' 1927.,

UNITED STATES` CITY, NEW JERSEY, ASSIGNOR TO TE BABCOCK &

DAVID S. il'ACoBUs, OF JERSEY Locri WILCOX COMPANY, 0F BAYONNE, NEW JERSEY; A CORPORATION OF NEW IFERSIIYY.A

METHOD AND APPARATUS Fon BURNING FUEL.` d

Application led July 19,

have an oxygen content greater than normal." In .the following description and .the appended claims, I have, for brevity, called such oxygen-enriched air superoxygenized or superoxygenated. The production of such enriched air takes energy, hoWever,`and 'it is one of the purposes of my invention to provide a methodand apparatus by which such enriched air may be used advantageously and with a minimum consumption of such As. -illustrative embodiment of my invention, I have shown it applied 'to a chain.- grate mechanical Stoker' used in connection with a Water tube boiler.

-In the drawing which shows a vertical section'of such a grate and portions of the surroundin furnace and boiler, 10-1() represent the boiler tubes. The furnace front Wall 11 has a combustion arch 12 belovv it onv which is supported a hopper 13 provided With an adjustable' gate 14 through which the fuel mayflow to the grate. A bridge wall 15 is provided with a Water cooled-fuel back'l.

The chain-grate'17 is mounted on sprocket Wheels 18, 19 which are moved either intermittently or continuously in the Well-known manner.

The space between'the lupper and-loiverruns of the chain 17 is divided into a plurality of air supply boxes 20,21, 22 and 23 provided with suitable means for keeping the air supply in each separate from the other boxes, the grate being arranged so thatthe' air in a givenair supply box will passup only through the portion of the grate above it.

Below the grate is a forced-draftair supply box 24 connected by lducts 25, 26, 27 and 28, respectively, with the several air supply boxes 20, 21, 22 and 23.

A duct 29 lthrough which the enriched superoxygenized air will be supplied under pressure is provided, the duct 29 being connected, in the illustrative form, to the ducts 25 and 26 by a cross duct 30, dampers 31 and 32 being provided in the duct'30.

If desired, the duct 29, could be' connected l may be individual 1921. serial No. 4a5,s69.

.with either or both of the ducts 27 and 28 also. Preferablyda1npe`rs will bqprovided I in each of the ducts 25,26, 27 an'd 2 8, all of the dampers havin provision'l by which Vthey Iyoperated by the opera-v tor of the furnace. v

In operation, the'upper run of the .chain will be moved from the -leftto the right of the gure, the fuel being suppliedfrom I the i hopper 13 on the leftfhand endand the ashes and refuse being depositedin the ash-pit'at the right-hand'endof the grate.

l vlVith the dampers set in the position. shown in the figures, normal air Will be sup-4 plied through the ducts 26,27 and 28 tothe boxes 21, -22, and 23 so that the fuel bed above such boxes-will be. supplied onlyvvith air having a normal oxygen content. .By li' reason of the closure of the-dan1 er'in the duct 25 and the opening of the amper 32,. as shown in. the figure, superoxygenized air" will be supplied tothe box 20'and the fuel I above that box Will therefore be supplied vvith enriched air only. If desired, the rela-5v f' t1ve amountsof enriched air and the number of boxes to which it is to be supplied may be regulated by the dampers inthe ducts v25, 26 and 30.- it being apparent that if, for

instance, the damper 31 is'partly open and i the damper in the duct 26 is alsopartly open, the box 21 will be' Supplied with air somewhat richer in oxygen than the normal'air but less in-oxygen content than the air' supplied to the box 20 with'the d'ampers' in the position show-n inthe figure.

the arrangement which I have described, the fresh fuel is ignited Vin"the pres? ence of the superoxygenized air, and as such ignited fuel is carried successively over the different air supply boxes, the oxygenfcontent of the air supply WillY be decreased tonorma'l, so' that the remaining portionsof the fuel bed Willbe consumed in the presence of a smaller proportion of oxygen.A

Such an arrangement is articularly. advantageous in connection with certain fuels which are comparatively diiicult to ignite, but which burnl readily after they are ignited.

Byy my method such fuels 'ma be more read-.

ily ignited so that the capaelty of the' grate.

may be ,greatly increased.

It will also. be seen that s'ince'I use the i A superoxygenized airunder only a portion of the fuel bed, Athe total amount of such en-v riched airused is greatly decreased over indeed, to any air -Were suppliedun'der the entire fuel b'ed.

While I have illustratedmy inventionfin connection with a chain-grate' furnace, it., 'will be understood that it may 'be `applied to other forms of mechan'ical" stokers and',". form of fuel bed in which the different parts of thefuel-bed may be supv -plied with different qualities of air andfin Which the fuel may-be moved from one kind of air supply to another.v -My invention .will

' .the excess oxygenwouldfirst eieet the ra id i 1 ignition j and consequentfdrying of 'the u el .15 the.' grate which have asupply of'normal air;

before the fuelis'carriedfto the portions of;

,1; In a-furnace, grate on'which air may be supplied t one partof thefuel on said grate and ai-ryvith'a normal c )giygner-1'l I. content. suppliedto the 'remainder of the fuel, and meas whereby the oxygen content of superoirygenized air may be varied `lby theo erator ofthe furnace.

2; n a furnace, a. grate on whichthe'fuel is burned, means `Whereby vsuperoxygenized4 1 "air may be supplied on said grate and 'air with a normal oxygenl to' one part of the fuel content Isupplied to theremainder of the fuelfandmeaus fw'hereby .thearea of-thej 'superoxygenized' to the remainder fuel bed, `and meaI1 S' -j )fuel to whichthe'supero'xy enized air 'isV bed andlair with thefurnace -what vvould be used ifisuch superoxygenized to move the fuel so that it Will first lo'eoonf.v tactedv by the superoxygen'ized air vand then.

by'the'n'ormal air. lLgfIna furnace, a mechanical stoker and means to'supply superoxygeniz'ed air to selected parts of the grate of said Stoker, said Stoker being arranged'to'present the fresh vfuel-to the Asuperoxygenized air supply and then to a normal air supply. A 5. In'afurnace,4 'a mechanical Stoker 'arranged-to support fuel onl agrate and move also be applicable to Wet fuels,- in- Whioh ca'sefit f into thel furnace, ,andv ducts to 'Supply superoxygenized air-"to the fuel as it enters between the upper and lower Supply. boxesj grate, COnduts for supplying rims n the atmospheric j air and'fsuperoxygenated alrs'eparately to-said boxes, and means for regulatin'g' 'the' supply of' each lsort of air `to saidboxe's.

. l7.','Ihe method of burning fuel- Which comy vprisesigniti'ng the fuel in l.thef-presence of content greaterV than thel (':ox'nbustiong` inthe Vpresenfeeof air yWit ess ogygen conv air`vvith .an ogygen Ynormal and then completi The method of burning fuel Which'comi `prises igniting the fuel in the presence ofair 'with 'an oxygen content ,appreciably' in excessfof normall atmosphere and then movwith less oxygen content to complete the combustion.

' DAVID s. .iA- conos and, then normal air after the fuelhas been-ignited in the presence of the -ingthe ignited fuelinto the presence of air 

